[PATCH 1/8] net: validate MAC address directly in dev_set_mac_address()

[Danny Kukawka <danny.kukawka@bisect.de>]

Validate the given MAC address directly in dev_set_mac_address()
if a .ndo_validate_addr function is available before calling
the .ndo_set_mac_address function.

Changed .ndo_validate_addr to take a second parameter containing
a sockaddr struct to be checked instead of the net_device dev_addr.
The behaviour of .ndo_validate_addr is now: if the second parameter
is NULL the net_device->dev_addr gets validate, if != NULL
the given parameter/sockaddr gets validated instead.

Removed is_valid_ether_addr() check from eth_mac_addr() since
this is now done in dev_set_mac_address(). Adapted eth_validate_addr()
to the changes.

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
---
 include/linux/etherdevice.h |    2 +-
 include/linux/netdevice.h   |    7 +++++--
 net/core/dev.c              |    7 ++++++-
 net/ethernet/eth.c          |   12 +++++++++---
 4 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h
index 8a18358..ee3091f 100644
--- a/include/linux/etherdevice.h
+++ b/include/linux/etherdevice.h
@@ -44,7 +44,7 @@ extern void eth_header_cache_update(struct hh_cache *hh,
 				    const unsigned char *haddr);
 extern int eth_mac_addr(struct net_device *dev, void *p);
 extern int eth_change_mtu(struct net_device *dev, int new_mtu);
-extern int eth_validate_addr(struct net_device *dev);
+extern int eth_validate_addr(struct net_device *dev, void *addr);
 
 
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index f1b7d03..08186e3 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -772,8 +772,10 @@ struct netdev_fcoe_hbainfo {
  *	needs to be changed. If this interface is not defined, the
  *	mac address can not be changed.
  *
- * int (*ndo_validate_addr)(struct net_device *dev);
+ * int (*ndo_validate_addr)(struct net_device *dev, void *addr);
  *	Test if Media Access Control address is valid for the device.
+ *      If addr is NULL the Media Access Control address of the device
+ *      get validated, otherwise the MAC of the net_device.
  *
  * int (*ndo_do_ioctl)(struct net_device *dev, struct ifreq *ifr, int cmd);
  *	Called when a user request an ioctl which can't be handled by
@@ -919,7 +921,8 @@ struct net_device_ops {
 	void			(*ndo_set_rx_mode)(struct net_device *dev);
 	int			(*ndo_set_mac_address)(struct net_device *dev,
 						       void *addr);
-	int			(*ndo_validate_addr)(struct net_device *dev);
+	int			(*ndo_validate_addr)(struct net_device *dev,
+						     void *addr);
 	int			(*ndo_do_ioctl)(struct net_device *dev,
 					        struct ifreq *ifr, int cmd);
 	int			(*ndo_set_config)(struct net_device *dev,
diff --git a/net/core/dev.c b/net/core/dev.c
index 763a0ed..b26a287 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1162,7 +1162,7 @@ static int __dev_open(struct net_device *dev)
 	set_bit(__LINK_STATE_START, &dev->state);
 
 	if (ops->ndo_validate_addr)
-		ret = ops->ndo_validate_addr(dev);
+		ret = ops->ndo_validate_addr(dev, NULL);
 
 	if (!ret && ops->ndo_open)
 		ret = ops->ndo_open(dev);
@@ -4820,6 +4820,11 @@ int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
 		return -EINVAL;
 	if (!netif_device_present(dev))
 		return -ENODEV;
+	if (ops->ndo_validate_addr) {
+                err = ops->ndo_validate_addr(dev, sa);
+		if (err)
+			return err;
+	}
 	err = ops->ndo_set_mac_address(dev, sa);
 	if (!err)
 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index a93af86..d25cc7a 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -285,8 +285,6 @@ int eth_mac_addr(struct net_device *dev, void *p)
 
 	if (netif_running(dev))
 		return -EBUSY;
-	if (!is_valid_ether_addr(addr->sa_data))
-		return -EADDRNOTAVAIL;
 	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 	/* if device marked as NET_ADDR_RANDOM, reset it */
 	dev->addr_assign_type &= ~NET_ADDR_RANDOM;
@@ -311,8 +309,16 @@ int eth_change_mtu(struct net_device *dev, int new_mtu)
 }
 EXPORT_SYMBOL(eth_change_mtu);
 
-int eth_validate_addr(struct net_device *dev)
+int eth_validate_addr(struct net_device *dev, void *addr)
 {
+	struct sockaddr *saddr;
+
+	if (addr) {
+		saddr = addr;
+		if (!is_valid_ether_addr(saddr->sa_data))
+			return -EADDRNOTAVAIL;
+	}
+
 	if (!is_valid_ether_addr(dev->dev_addr))
 		return -EADDRNOTAVAIL;
 
-- 
1.7.8.3